7mm sherman max

[elkaholic]

Looks like RL23 has some potential up to 3050'. Also, shot one group of N 560 which looks pretty good. This was a moderate load. Looks like it would run up to mid or high 3000's.

 

[highdrum]

What twist is your proof research, I'm thinking about getting one for this same build. Thinking about going with an 8 twist.

It's a proof sendero 1:8 26"

 

[elkaholic]

Im getting the 195 dialed in a little. This is a moderate pressure load
THIS BARREL IS LIKELY 2 GRAINS HIGHER IN CHARGE TO PRESSURE UP THAN MOST!
We have an identical barrel in a 7 ss thats the same way!!!

 

[Korhil78]

You are using regular large rifle primers instead of magnum?

 

[elkaholic]

You are using regular large rifle primers instead of magnum?

i did today. the 195's tightened up a little too

 

[elkaholic]

The Max shot pretty well with RL25 today with 175 EH's and also shot well with RL23 and 175 eldx. First try with this bullet.

i wish I had some more RL26 to test for accuracy because the velocity was there before I ran out.
N560 ran the 195 north of 2900 today but didnt test for accuracy yet.

 

[elkaholic]

I tried to pressure the Max out today by using a drop tube and got some crazy numbers!! The 195 had some heaviness in the bolt but no X mark and the 175 EH didnt even have a heavy bolt!
The charges were 71 and 72 grs N570.
Again, I expect most barrels will max out 2 grains lower.
i also shot a 3 shot group with a 70 grain charge while I was there and they went into the usual .3 moa
I wouldnt run them at those top loads but it gives me confidence at 50' slower.

Speed on target should be 2983 not 3083'

 

[highdrum]

Rich, you should build this in a 30 cal as well! Too bad ADG doesn't make 300 saum parent case......boo

 

[elkaholic]

Rich, you should build this in a 30 cal as well! Too bad ADG doesn't make 300 saum parent case......boo

i have 300 and 338 reamers

 

[Korhil78]

So you got the 195 up to 3050 and the 175 up to 3150?

 

[elkaholic]

So you got the 195 up to 3050 and the 175 up to 3150?

yep. Like I said, im not suggesting anyone try to run them there but i now know there is a cushion if someone wanted to run 3000' and 3100' with that powder.

 

[highdrum]

i have 300 and 338 reamers

Brass suggestions for the 300? Is norma 300 saum up to snuff to push 200gr pills north of 3k in a 23" barrel?

 

[elkaholic]

Brass suggestions for the 300? Is norma 300 saum up to snuff to push 200gr pills north of 3k in a 23" barrel?

just buy the 7 max brass and neck it up.
im not sure about 3000' with a 23" barrel though? 25" maybe

 

[OhYtD]

As I was making some brass today I pondered the idea of making brass for people. I even thought about a dedicated fireforming barrel and stainless steel pin cleaning so the person gets what looks to be brand new brass ready to go. Then, after thinking about it a bit more, I realized it would cost the person close to the price of ADG brass if you factor in my powder, primer, bullets, barrel wear and time.